If you attempt to manually confirm a stock count and a screen like the one above pops up, it usually means that you have entered the count for that stock code into the first tab (Stock) and not into the second tab (Serialised, Special, Adjustment).
You will not be able to continue until you rectify the situation, which you can do in one of two ways:
1.If you only have a small quantity of stock in this stocktake session, you can click Generate Stock List which will delete all counts previously entered, then simply re-enter the counts making sure that you do this using the second tab where applicable).
2.If it's not practical to use the method above, then you will need to manually delete the count for each stock code that is giving you the error message and enter the stock count again, this time ensuring that you choose the second tab.
See Deleting & Re-entering Counts for details.